Stressing out

Waiting to find out if my 3 year old has mono or strep. I have a one month old too. I am home on leave, so home alone while my husband is at work. My 3 year old obviously feels horrible, and just wants to sit with me all day. He cries if I tell him I have to take care of the baby and can't snuggle him. I just feel so bad. I was told chances are the baby will get mono too, and we are at risk. He most likely contracted it at daycare since that is the only place he has really been other than home.